1. Field of the Invention
This invention relates to a method and an apparatus for a fixed combination of side-fold bags to form stacks, wherein the side-fold bags to be combined, which are coming from a machine which produces side-fold bags, have previously been separated into stacks of controllable quantity, and wherein during combining each stack is oriented in relation to a perforating station and is pressed together.
2. Description of Prior Art
In order to be able to automatically package goods, for example bread, it is necessary that the packaging is accurately oriented and is easy to handle. The automatic packaging of goods in paper or plastic bags in particular makes high demands. Generally, bags which have a side fold are used for this purpose, having one side at the open end of the bag which is not folded and forms a protruding tongue. Such bags are called side-fold bags. To allow automatic packaging, several side-fold bags are combined to form a stack by guiding a metal hoop through two holes punched into protruding tongues lying on top of each other. During packaging, a stack of side-fold bags is held in the packaging device in such a way that the side-fold bags lie flat on a packaging table with their sides having tongues down, and the open ends of the metal hoop project downward. The topmost side-fold bag is opened by blowing in air and the goods are inserted. Thereafter the side-fold bag with the goods is pulled away from the metal hoop in the longitudinal direction and the holes are ripped open in the process. Now the bag next below is inflated and goods packed in it.
The metal hoop assures that the respectively topmost bag can be inflated, while the lower, punched lateral surface is kept on the packaging table. The hoop additionally maintains the bags in a fixed position and allows the tearing off of the uppermost bag in a well-defined direction.
The stacks have the metal hoops during their manufacture and packing. To this end bags produced by the machine producing side-fold bags are counted in a counting device, counted stacks are pressed together, the protruding tongues are provided with two punched holes and a metal hoop is manually guided through the holes. For fixing the stack in place, a rubber band is manually wound around the open ends of the metal hoop. Thereafter the bundled stacks are packed and delivered to the packager.
The packaging method using metal hoops has proven itself but is disadvantageous because the metal hoops are awkward and therefore make the packing of the stacks more difficult. The fact that some steps must be manually performed further increases the packing costs. In addition, the metal hoop increases the total weight, which in turn increases transportation costs. It is furthermore necessary that the metal hoops be returned from the packager to the bag manufacturer to be reused.